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1.
J Behav Med ; 46(4): 566-577, 2023 Aug.
Article in English | MEDLINE | ID: mdl-36414833

ABSTRACT

The purpose of this investigation was to explore the effects of dietary weight loss intervention, with and without the addition of exercise on health-related quality of life, depressive symptoms, and anxiety. As part of the EMPOWER study for women, sixty premenopausal women (BMI of 40.4 ± 6.7) were randomized to energy restriction only (ER) or to exercise plus energy restriction (EXER) for 12 months. Health-related quality of life was assessed using the SF-36, depressive symptoms were assessed using the Beck Depression Inventory II (BDI), and anxiety symptoms using the Spielberger state and trait anxiety questionnaire. All measures were completed at baseline, 3, 6 and 12 months. At 12 months, there were significant (p < 0.05) group-by-time interactions favouring the EXER group for five of the eight domains and the mental component summary score. At 12 months, a significant group-by-time interaction favouring the EXER group is reported for both state and trait anxiety (p = .005 and p = .001, respectively). At 12 months, there was a significant group-by-time interaction for depressive symptoms favouring EXER (p < 0.05). Within-group changes for BDI scores were improved at all follow-up time points in the EXER group. Exercise training confers an additional benefit to energy restriction in the absence of additional weight loss at 12 months for health-related quality of life, depressive symptoms, and state and trait anxiety scores when compared to energy restriction only. Exercise and an energy-restricted diet improve health-related quality of life and mental health. Exercise may protect mental health without further weight loss for women with severe obesity.


Subject(s)
Obesity, Morbid , Female , Humans , Quality of Life , Mental Health , Obesity/complications , Obesity/therapy , Weight Loss , Depression
2.
Clin Auton Res ; 32(1): 29-42, 2022 02.
Article in English | MEDLINE | ID: mdl-34762216

ABSTRACT

PURPOSE: Abnormalities in autonomic function have been observed in people with anorexia nervosa. However, the majority of investigations have utilised heart rate variability as the sole assessment of autonomic activity. The current study utilised a variety of methodologies to assess autonomic nervous system function in women with a current diagnosis of anorexia, a past diagnosis of anorexia who were weight-restored, and healthy controls. METHODS: The sample included 37 participants: 10 participants with anorexia, 17 weight-restored participants (minimum body mass index > 18.5 for minimum of 12 months) and 10 controls. Assessments of autonomic function included muscle sympathetic nerve activity (MSNA) using microneurography, heart rate variability, baroreflex sensitivity, blood pressure variability, head-up tilt table test, sudomotor function and assessment of plasma catecholamines. RESULTS: MSNA (bursts/min) was significantly decreased in both anorexia (10.22 ± 6.24) and weight-restored (17.58 ± 1.68) groups, as compared to controls (23.62 ± 1.01, p < 0.001 and p = 0.033, respectively). Participants with anorexia had a significantly lower standard deviation in heart rate, lower blood pressure variability and decreased sudomotor function as compared to controls. Weight-restored participants demonstrated decreased baroreflex sensitivity in response to head-up tilt as compared to controls. CONCLUSION: Women with a current or previous diagnosis of anorexia have significantly decreased sympathetic activity, which may reflect a physiological response to decreased energy intake. During the state of starvation, women with anorexia also displayed decreased sudomotor function. The consequences of a sustained decrease in MSNA are unknown, and future studies should investigate autonomic function in long-term weight-restored participants to determine whether activity returns to normal.


Subject(s)
Anorexia Nervosa , Anorexia , Autonomic Nervous System/physiology , Baroreflex/physiology , Blood Pressure , Female , Heart Rate/physiology , Humans , Sympathetic Nervous System
3.
J Physiol ; 599(15): 3755-3770, 2021 08.
Article in English | MEDLINE | ID: mdl-34101823

ABSTRACT

KEY POINTS: Controversy exists about the physiological mechanism(s) underlying decreases in cardiac output after immediate clamping of the umbilical cord at birth. To define these mechanisms, the four major determinants of ventricular output (afterload, preload, heart rate and contractility) were measured concurrently in fetal lambs at 15 s intervals over a 2 min period after cord clamping and before ventilation following delivery. After cord clamping, right (but not left) ventricular output fell by 20% in the initial 30 s, due to increased afterload associated with higher arterial blood pressures, but both outputs then halved over 45 s, due to a falling heart rate and deteriorating ventricular contractility accompanying rapid declines in arterial oxygenation to asphyxial levels. Ventricular outputs subsequently plateaued from 75 to 120 s, associated with rebound rises in ventricular contractility accompanying asphyxia-induced surges in circulating catecholamines. These findings provide a physiological basis for the clinical recommendation that effective ventilation should occur within 60 s after immediate cord clamping. ABSTRACT: Controversy exists about the physiological mechanism(s) underlying large decreases in cardiac output after immediate clamping of the umbilical cord at birth. To define these mechanisms, anaesthetized preterm fetal lambs (127(1)d, n = 12) were instrumented with flow probes and catheters in major central arteries, and a left ventricular (LV) micromanometer-conductance catheter. Following immediate cord clamping at delivery, haemodynamics, LV and right ventricular (RV) outputs, and LV contractility were measured at 15 s intervals during a 2 min non-ventilatory period, with aortic blood gases and circulating catecholamine (noradrenaline and adrenaline) concentrations measured at 30 s intervals. After cord clamping, (1) RV (but not LV) output fell by 20% in the initial 30 s, due to a reduced stroke volume associated with increased arterial blood pressures, (2) both outputs then halved over the next 45 s, associated with falls in heart rate, arterial blood pressures and ventricular contractility accompanying a rapid decline in arterial oxygenation to asphyxial levels, (3) reduced outputs subsequently plateaued from 75 to 120 s, associated with rebound rises in blood pressures and ventricular contractility accompanying exponential surges in circulating catecholamines. These findings are consistent with a time-dependent decline of ventricular outputs after immediate cord clamping, which comprised (1) an initial, minor fall in RV output related to altered loading conditions, (2) ensuing large decreases in both LV and RV outputs related to the combination of bradycardia and ventricular dysfunction during emergence of an asphyxial state, and (3) subsequent stabilization of reduced LV and RV outputs during ongoing asphyxia, supported by cardiovascular stimulatory effects of marked sympathoadrenal activation.


Subject(s)
Fetus , Heart Ventricles , Animals , Animals, Newborn , Cardiac Output , Constriction , Female , Hemodynamics , Humans , Sheep
4.
Circulation ; 141(17): 1393-1403, 2020 04 28.
Article in English | MEDLINE | ID: mdl-32093510

ABSTRACT

BACKGROUND: High blood pressure (BP) continues to be a major, poorly controlled but modifiable risk factor for cardiovascular death. Among key Western lifestyle factors, a diet poor in fiber is associated with prevalence of high BP. The impact of lack of prebiotic fiber and the associated mechanisms that lead to higher BP are unknown. Here we show that lack of prebiotic dietary fiber leads to the development of a hypertensinogenic gut microbiota, hypertension and its complications, and demonstrate a role for G-protein coupled-receptors (GPCRs) that sense gut metabolites. METHODS: One hundred seventy-nine mice including C57BL/6J, gnotobiotic C57BL/6J, and knockout strains for GPR41, GPR43, GPR109A, and GPR43/109A were included. C57BL/6J mice were implanted with minipumps containing saline or a slow-pressor dose of angiotensin II (0.25 mg·kg-1·d-1). Mice were fed diets lacking prebiotic fiber with or without addition of gut metabolites called short-chain fatty acids ([SCFA)] produced during fermentation of prebiotic fiber in the large intestine), or high prebiotic fiber diets. Cardiac histology and function, BP, sodium and potassium excretion, gut microbiome, flow cytometry, catecholamines and methylation-wide changes were determined. RESULTS: Lack of prebiotic fiber predisposed mice to hypertension in the presence of a mild hypertensive stimulus, with resultant pathological cardiac remodeling. Transfer of a hypertensinogenic microbiota to gnotobiotic mice recapitulated the prebiotic-deprived hypertensive phenotype, including cardiac manifestations. Reintroduction of SCFAs to fiber-depleted mice had protective effects on the development of hypertension, cardiac hypertrophy, and fibrosis. The cardioprotective effect of SCFAs were mediated via the cognate SCFA receptors GPR43/GPR109A, and modulated L-3,4-dihydroxyphenylalanine levels and the abundance of T regulatory cells regulated by DNA methylation. CONCLUSIONS: The detrimental effects of low fiber Westernized diets may underlie hypertension, through deficient SCFA production and GPR43/109A signaling. Maintaining a healthy, SCFA-producing microbiota is important for cardiovascular health.


Subject(s)
Dietary Fiber/deficiency , Fatty Acids, Volatile/metabolism , Gastrointestinal Microbiome , Hypertension , Intestinal Mucosa , Prebiotics , Receptors, G-Protein-Coupled/metabolism , Signal Transduction , Animals , Hypertension/genetics , Hypertension/metabolism , Hypertension/microbiology , Hypertension/pathology , Intestinal Mucosa/metabolism , Intestinal Mucosa/microbiology , Intestinal Mucosa/pathology , Male , Mice , Mice, Knockout , Receptors, G-Protein-Coupled/genetics
5.
Am J Physiol Heart Circ Physiol ; 320(2): H891-H900, 2021 02 01.
Article in English | MEDLINE | ID: mdl-33566748

ABSTRACT

People with intellectual disability (ID) experience cardiometabolic-related morbidity and mortality. However, it has been suggested that this population presents and lives with underestimated cardiovascular risk factors at a younger age, hence affecting their overall health and quality of life and contributing to early mortality. We assessed autonomic nervous system function in subjects with ID (n = 39), aged 18-45 yr, through measures of sudomotor function, heart rate and systolic blood pressure variability, and cardiac baroreflex function. Traditional clinical cardiovascular measurements and a biochemical analysis were also undertaken. We found that young adults with ID presented with sudomotor dysfunction, impaired cardiac baroreflex sensitivity, and systolic blood pressure variability, when compared with age-matched control subjects (n = 38). Reduced hand and feet electrochemical skin conductance and asymmetry were significantly associated with having a moderate-profound ID. Autonomic dysfunction in individuals with ID persisted after controlling for age, sex, and other metabolic parameters. Subjects in the ID group also showed significantly increased blood pressure, body mass index, and waist/hip circumference ratio, as well as increased plasma hemoglobin A1c and high-sensitivity C-reactive protein levels. We conclude that autonomic dysfunction is present in young adults with ID and is more marked in those with more severe disability. These finding have important implications in developing preventative strategies to reduce the risk of cardiovascular disease in people with ID.NEW & NOTEWORTHY Adults with intellectual disability experience higher risk of premature death than the general population. Our investigation highlights increased cardiovascular risk markers and autonomic dysfunction in young adults with intellectual disability compared with control adults. Autonomic dysfunction was more marked in those with a more severe disability but independent of cardiovascular parameters. Assessment of autonomic nervous system (ANS) function may provide insight into the mechanisms of cardiometabolic disease development and progression in young adults with intellectual disability.


Subject(s)
Autonomic Nervous System Diseases/etiology , Autonomic Nervous System/physiopathology , Cardiovascular Diseases/etiology , Cardiovascular System/innervation , Intellectual Disability/complications , Persons with Mental Disabilities , Sweat Glands/innervation , Adolescent , Adult , Age Factors , Autonomic Nervous System Diseases/diagnosis , Autonomic Nervous System Diseases/physiopathology , Baroreflex , Blood Pressure , Cardiovascular Diseases/diagnosis , Cardiovascular Diseases/physiopathology , Case-Control Studies , Cross-Sectional Studies , Female , Heart Disease Risk Factors , Heart Rate , Humans , Intellectual Disability/diagnosis , Male , Middle Aged , Risk Assessment , Severity of Illness Index , Sweating , Young Adult
6.
BMC Public Health ; 21(1): 2326, 2021 12 30.
Article in English | MEDLINE | ID: mdl-34969382

ABSTRACT

BACKGROUND: The use of digital interventions for managing chronic diseases is significantly increasing. The aim of this study was to estimate the proportion of ownership of a mobile phone, and factors associated with the ability to read and access SMS delivered health information, and willingness to pay for it among people with hypertension in a rural area in Bangladesh. METHODS: Data were collected from 307 participants aged 30 to 75 years with hypertension from a rural area in Bangladesh from December 2020 to January 2021. Outcome measures included ownership of a mobile phone, ability to read SMS, willingness to receive and pay for health information by SMS. Associated factors included age, gender, level of education, occupation, and socioeconomic status. We used regression analysis to identify variables associated with the outcome variables. RESULTS: Overall, 189 (61.6%) people owned a mobile phone which was higher in men (73.3% vs. 50%, p < 0.001), younger people (82.6% aged 30-39 years vs. 53.5% aged 60-75 years, p < 0.001). Of the total participants, 207 (67.4%) were willing to receive SMS, and 155 (50.5%) were willing to pay for receiving SMS for health information. The prevalence was significantly higher among professionals (odds ratio (OR), 95% confidence interval (CI): 4.58, 1.73-12.1) and businesspersons (OR 3.68, 95% CI 1.49-9.10) compared to farmers, respectively. The median (interquartile range [IQR]) of willingness to pay for health information SMS was 10 (28) Bangladesh Taka (BDT) (1 BDT ~ 0.013 US$), and there were no specific factors that were associated with the willingness of any higher amounts of payment. In terms of reading SMS of people who own a mobile, less than half could read SMS. The proportion of people who could read SMS was significantly higher among men, younger people, educated people, middle class or rich people, professionals or businesspersons. Of people who could read SMS, the majority read SMS occasionally. CONCLUSION: A significant proportion of people are unable to read SMS. However, people are willing to receive and pay to receive SMS for health information. Education and awareness programs should be conducted among targeted groups, including people with low education and women.


Subject(s)
Cell Phone , Text Messaging , Adult , Aged , Bangladesh/epidemiology , Educational Status , Female , Humans , Intention , Male , Middle Aged , Sociodemographic Factors
7.
BMC Public Health ; 21(1): 2316, 2021 12 23.
Article in English | MEDLINE | ID: mdl-34949160

ABSTRACT

BACKGROUND: The use of antihypertensive medications is critical for controlling high blood pressure. We aimed to investigate associations between socio-demographic factors and antihypertensive medications use, and antihypertensive medications use with different types of drugs use with levels of systolic blood pressure (SBP) and diastolic blood pressure (DBP). METHODS: For the present report we derived data from the baseline measurements of a cluster randomised control trial on 307 participants with previously diagnosed hypertension from the rural district of Narial in Bangladesh. We measured the participant's current blood pressure levels and recorded antihypertensive medications uses. Associated factors included socio-economic status, diabetes, antihypertensive medications use, and types of drugs and doses used for controlling blood pressure. We applied analysis of variance and logistic regression techniques to identify factors associated with blood pressure. RESULTS: Of the total participants, 144 (46.9%) were on antihypertensive medications. After multivariate adjustment, binary logistic regression revealed that employees (odds ratio, (95% confidence interval (CI)) (OR 3.58, 95%CI 1.38-9.28) compared to farmers, and people with diabetes (OR 2.43, 95%CI 1.13-5.26) compared to people without diabetes were associated with a higher proportion of antihypertensive medications use. Of 144 participants on antihypertensive medications, 7 (5%) had taken two doses, 114 (79%) had taken one dose per day and the rest were irregular in medication use. The mean (standard deviation) [min, max] SBP and DBP were 149 (19) mmHg [114, 217] and 90 (10) mmHg [75, 126], respectively. Overall, there was no significant difference in SBP (p = 0.10) or DBP (p = 0.67) between participants with or without antihypertensive medications or using any type of medications (p = 0.54 for SBP and 0.76 for DBP). There was no significant association between antihypertensive medications use and elevated BP levels SBP/DBP≥140/90 mmHg (p = 0.42) CONCLUSION: Less than half of the people with hypertension were on medication. Irrespective of the antihypertensive medications use, most of the participant's blood pressure was high. Further study is needed with a large sample to understand the factors and aetiology of unmanaged hypertension in rural areas of Bangladesh where the prevalence of hypertension is very high.


Subject(s)
Diabetes Mellitus , Hypertension , Antihypertensive Agents/therapeutic use , Bangladesh/epidemiology , Blood Pressure , Diabetes Mellitus/drug therapy , Humans , Hypertension/drug therapy , Hypertension/epidemiology
8.
Int J Mol Sci ; 22(8)2021 Apr 19.
Article in English | MEDLINE | ID: mdl-33921881

ABSTRACT

Metabolic dysfunction-associated fatty liver disease (MAFLD) is the most common liver disease affecting a quarter of the global population and is often associated with adverse health outcomes. The increasing prevalence of MAFLD occurs in parallel to that of metabolic syndrome (MetS), which in fact plays a major role in driving the perturbations of cardiometabolic homeostasis. However, the mechanisms underpinning the pathogenesis of MAFLD are incompletely understood. Compelling evidence from animal and human studies suggest that heightened activation of the sympathetic nervous system is a key contributor to the development of MAFLD. Indeed, common treatment strategies for metabolic diseases such as diet and exercise to induce weight loss have been shown to exert their beneficial effects at least in part through the associated sympathetic inhibition. Furthermore, pharmacological and device-based approaches to reduce sympathetic activation have been demonstrated to improve the metabolic alterations frequently present in patients with obesity, MetSand diabetes. Currently available evidence, while still limited, suggests that sympathetic activation is of specific relevance in the pathogenesis of MAFLD and consequentially may offer an attractive therapeutic target to attenuate the adverse outcomes associated with MAFLD.


Subject(s)
Metabolic Syndrome/metabolism , Non-alcoholic Fatty Liver Disease/metabolism , Animals , Humans , Liver/innervation , Sympathetic Nervous System/metabolism
9.
Diabetologia ; 63(7): 1424-1434, 2020 07.
Article in English | MEDLINE | ID: mdl-32372207

ABSTRACT

AIMS/HYPOTHESIS: We determined whether empagliflozin altered renal sympathetic nerve activity (RSNA) and baroreflexes in a diabetes model in conscious rabbits. METHODS: Diabetes was induced by alloxan, and RSNA, mean arterial pressure (MAP) and heart rate were measured before and after 1 week of treatment with empagliflozin, insulin, the diuretic acetazolamide or the ACE inhibitor perindopril, or no treatment, in conscious rabbits. RESULTS: Four weeks after alloxan administration, blood glucose was threefold and MAP 9% higher than non-diabetic controls (p < 0.05). One week of treatment with empagliflozin produced a stable fall in blood glucose (-43%) and increased water intake (+49%) but did not change RSNA, MAP or heart rate compared with untreated diabetic rabbits. The maximum RSNA to hypotension was augmented by 75% (p < 0.01) in diabetic rabbits but the heart rate baroreflex was unaltered. Empagliflozin and acetazolamide reduced the augmentation of the RSNA baroreflex (p < 0.05) to be similar to the non-diabetic group. Noradrenaline (norepinephrine) spillover was similar in untreated diabetic and non-diabetic rabbits but twofold greater in empagliflozin- and acetazolamide-treated rabbits (p < 0.05). CONCLUSIONS/INTERPRETATION: As empagliflozin can restore diabetes-induced augmented sympathetic reflexes, this may be beneficial in diabetic patients. A similar action of the diuretic acetazolamide suggests that the mechanism may involve increased sodium and water excretion. Graphical abstract.


Subject(s)
Benzhydryl Compounds/therapeutic use , Glucosides/therapeutic use , Animals , Baroreflex/drug effects , Blood Glucose/drug effects , Blood Pressure/drug effects , Body Weight/drug effects , Heart Rate/drug effects , Male , Perindopril/pharmacology , Rabbits , Sodium-Glucose Transporter 2 Inhibitors/pharmacology , Sympathetic Nervous System/drug effects , Sympathetic Nervous System/metabolism
10.
Kidney Int ; 98(4): 906-917, 2020 10.
Article in English | MEDLINE | ID: mdl-32763117

ABSTRACT

Chronic kidney disease (CKD) is associated with greater sympathetic nerve activity but it is unclear if this is a kidney-specific response or due to generalized stimulation of sympathetic nervous system activity. To determine this, we used a rabbit model of CKD in which quantitative comparisons with control rabbits could be made of kidney sympathetic nerve activity and whole-body norepinephrine spillover. Rabbits either had surgery to lesion 5/6th of the cortex of one kidney by electro-lesioning and two weeks later removal of the contralateral kidney, or sham lesioning and sham nephrectomy. After three weeks, the blood pressure was statistically significantly 20% higher in conscious rabbits with CKD compared to rabbits with a sham operation, but their heart rate was similar. Strikingly, kidney nerve activity was 37% greater than in controls, with greater burst height and frequency. Total norepinephrine spillover was statistically significantly lower by 34%, and kidney baroreflex curves were shifted to the right in rabbits with CKD. Plasma creatinine and urine output were elevated by 38% and 131%, respectively, and the glomerular filtration rate was 37% lower than in sham-operated animals (all statistically significant). Kidney gene expression of fibronectin, transforming growth factor-ß, monocyte chemotactic protein1, Nox4 and Nox5 was two- to eight-fold greater in rabbits with CKD than in control rabbits. Overall, the glomerular layer lesioning model in conscious rabbits produced a moderate, stable degree of CKD characterized by elevated blood pressure and increased kidney sympathetic nerve activity. Thus, our findings, together with that of a reduction in total norepinephrine spillover, suggest that kidney denervation, rather than generalized sympatholytic treatments, may represent a preferable management for CKD associated hypertension.


Subject(s)
Renal Insufficiency, Chronic , Animals , Baroreflex , Blood Pressure , Heart Rate , Kidney , Rabbits , Sympathetic Nervous System
11.
Eur Heart J Suppl ; 22(Suppl H): H17-H19, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32884459

ABSTRACT

May Measurement Month (MMM), originally initiated as a temporary solution to address the lack of blood pressure (BP) screening programs worldwide, emerged as an effective annual campaign to increase the awareness of hypertension. MMM18, a cross-sectional survey of volunteers aged ≥18 years was carried out during May 2018 predominantly in capital cities across Australia following the standard MMM protocol. Blood pressure screening along with additional information including anthropometric data and responses to questionnaires on demographic, lifestyle, and environmental factors were collected from 3 352 individuals across Australia. After multiple imputation, 1 026 (30.6%) adult Australians had hypertension. Of the 2 936 individuals not on antihypertensive treatment, 610 (20.8%) were hypertensive, and 237 (57.1%) of the 416 individuals receiving antihypertensive treatment had uncontrolled BP. In line with MMM17 results and other previous surveys, MMM18 revealed that close to one-third of the screened population (30.6%) had hypertension, 57.1% of individuals treated with BP-lowering medication remained uncontrolled indicating suboptimal management of the condition in the majority of patients. Most importantly, only 49.0% of those with hypertension were aware of their elevated BP, highlighting lack of awareness of elevated BP in nearly half of the affected population. Elevated BP was directly associated with alcohol consumption, overweight, and obesity. Our findings demonstrate the need for (i) continued efforts to increase BP awareness in the population, (ii) optimization of BP management strategies, and (iii) tackling some of the major contributors to BP elevation, including alcohol consumption and obesity.

12.
Clin Endocrinol (Oxf) ; 90(3): 425-432, 2019 03.
Article in English | MEDLINE | ID: mdl-30548504

ABSTRACT

OBJECTIVE: Polycystic ovary syndrome (PCOS) is associated with increased obesity with a greater propensity to weight gain and a lack of sustainable lifestyle interventions. Altered brown adipose tissue (BAT) thermogenesis is a potential contributor to obesity in PCOS. BAT activity and modulation have not been studied in PCOS. This observational study explored BAT thermogenesis and its associations in women with and without PCOS. PARTICIPANTS AND METHODS: Cutaneous temperature was recorded from supraclavicular (indicator of BAT activity) and upper arm regions using dataloggers (SubCue, Calgary, Canada) in a cross-sectional substudy, nested within a randomized control trial, of community-recruited premenopausal women with (n = 47, Rotterdam diagnostic criteria) and without (n = 11) PCOS. RESULTS: Complete temperature data were available in 44 PCOS (mean age: 30.0 ± 6.2, mean BMI: 29.3 ± 5.5) and 11 non-PCOS (mean age: 33.0 ± 7.0, mean BMI: 25 ± 3) women. Women with PCOS had lower supraclavicular skin temperature compared to controls overall (33.9 ± 0.7 vs 34.5 ± 1, P < 0.05) and during sleep (34.5 ± 0.6 vs 35.2 ± 0.9, P < 0.001). In the PCOS group, supraclavicular skin temperature overall and over sleep and waking hours correlated inversely with testosterone (r = -0.41 P < 0.05, r = -0.485 P < 0.01 and r = -0.450 P < 0.01 respectively). Testosterone levels explained approximately 15%, 30% and 20% of the variability in supraclavicular skin temperature overall and over sleep and waking hours in women with PCOS, respectively. CONCLUSION: Women with PCOS have lower BAT activity compared to controls. BAT thermogenesis is negatively associated with androgen levels in PCOS.


Subject(s)
Adipose Tissue, Brown/physiopathology , Polycystic Ovary Syndrome/physiopathology , Thermogenesis , Adult , Case-Control Studies , Female , Humans , Polycystic Ovary Syndrome/blood , Skin Temperature , Testosterone/blood , Young Adult
13.
Pediatr Res ; 86(4): 478-484, 2019 10.
Article in English | MEDLINE | ID: mdl-31181565

ABSTRACT

BACKGROUND: As surges in circulating norepinephrine and epinephrine have chronotropic, pressor, and inotropic effects, we tested the hypothesis that blunted rises in these catecholamines during preterm birth accompanied hemodynamic stability observed after early ventilation and delayed cord clamping (DCC), with findings compared to immediate cord clamping (ICC) and a non-asphyxial cord clamp-to-ventilation interval. METHODS: Anesthetized preterm fetal lambs were instrumented with arterial micromanometers to obtain pressure and the maximal rate of pressure rise (dP/dtmax) as a surrogate of ventricular contractility and an aortic catheter to obtain blood samples for catecholamine assay. Fetuses were delivered and mechanically ventilated before cord clamping ∼1.5 min later (DCC, n = 9) or subjected to ICC with ventilation started ∼40 s later (n = 8). RESULTS: Perinatal hemodynamics were stable after DCC, with greater fluctuations evident following birth after ICC (P ≤ 0.05). With DCC, circulating norepinephrine and epinephrine were unchanged after early ventilation but rose following cord clamping (P ≤ 0.01), with concentrations below the threshold for hemodynamic effects. Norepinephrine was higher in the ICC group after cord clamping and immediately after ventilation (P < 0.025), but catecholamine levels were otherwise similar between groups. CONCLUSION: Hemodynamic stability at birth after DCC is accompanied by sub-threshold rises in circulating norepinephrine and epinephrine and thus blunted sympathoadrenal activation.


Subject(s)
Epinephrine/blood , Norepinephrine/blood , Umbilical Cord , Adrenal Medulla/metabolism , Animals , Blood Pressure , Catecholamines/metabolism , Constriction , Female , Heart Rate , Hemodynamics , Male , Parturition , Pulmonary Ventilation , Respiration, Artificial , Sheep , Sympathetic Nervous System
14.
Arterioscler Thromb Vasc Biol ; 38(2): 438-447, 2018 02.
Article in English | MEDLINE | ID: mdl-29284607

ABSTRACT

OBJECTIVE: High-density lipoprotein (HDL) lipid composition and function may better reflect cardiovascular risk than HDL cholesterol concentration. This study characterized the relationships between HDL composition, metabolism, and function in metabolic syndrome (MetS) patients and how changes in composition after weight loss (WL) and exercise treatments are related to function. APPROACH AND RESULTS: Plasma samples from MetS patients (n=95) and healthy individuals (n=40) were used in this study. Subsets of the MetS group underwent 12 weeks of no treatment (n=17), WL (n=19), or WL plus exercise (WLEX; n=17). HDL was isolated using density-gradient ultracentrifugation. The HDL lipidome was analyzed by mass spectrometry, and particle size determined by nuclear magnetic resonance. Cholesteryl ester transfer protein activity and ex vivo HDL cholesterol efflux capacity (CEC) were assessed. The HDL lipidome in the MetS patients was substantially different from that in healthy individuals, mean particle size was smaller, and CEC was lower. Several HDL phospholipid and sphingolipid species were associated with HDL diameter and CEC. The HDL lipidome and particle size were modified toward the healthy individuals after WL and WLEX treatments, with greater effects observed in the latter group. Cholesteryl ester transfer protein activity was reduced after WL and WLEX, and CEC was improved after WLEX. CONCLUSIONS: WLEX treatment in MetS patients normalizes the HDL lipidome and particle size profile and enhances CEC. HDL lipids associated with diminished CEC may represent novel biomarkers for early prediction of HDL dysfunction and disease risk and may represent potential therapeutic targets for future HDL therapies. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00163943.


Subject(s)
Caloric Restriction , Exercise Therapy , Lipoproteins, HDL/blood , Metabolic Syndrome/therapy , Weight Loss , Biomarkers/blood , Cholesterol Ester Transfer Proteins/blood , Cholesterol, HDL/blood , Combined Modality Therapy , Female , Humans , Male , Metabolic Syndrome/blood , Metabolic Syndrome/diagnosis , Metabolic Syndrome/physiopathology , Middle Aged , Particle Size , Phospholipids/blood , Randomized Controlled Trials as Topic , Sphingolipids/blood , THP-1 Cells , Time Factors , Treatment Outcome
15.
Eur Heart J Suppl ; 21(Suppl D): D14-D16, 2019 Apr.
Article in English | MEDLINE | ID: mdl-31043866

ABSTRACT

Increased blood pressure (BP) is the single biggest contributing risk factor to the global disease burden. May Measurement Month (MMM) is a global initiative of the International Society of Hypertension aimed at raising awareness of high BP. In Australia, hypertension affects around six million adults and continues to remain the greatest attributable cause of cardiovascular mortality and morbidity (48.3%), stroke deaths (28%), and kidney disease (14%). An opportunistic cross-sectional survey was carried out during May 2017 predominantly in capital cities across Australia which included adult volunteers. Blood pressure measurement, the definition of hypertension and statistical analysis followed the standard MMM protocol. Additional information obtained included anthropometric data and responses to questionnaires on demographic, lifestyle, and environmental factors. Data were collected from 3817 individuals. After multiple imputation, of the 3758 individuals for whom a mean of the second and third BP reading was available, 1188 (31.2%) had hypertension. Of 3213 individuals not receiving antihypertensive treatment, 591 (18.4%) were hypertensive, and 239 (40.1%) of the 596 individuals receiving treatment had uncontrolled BP. Adjusted BP was higher in association with antihypertensive medication, cerebrovascular disease, smoking, and alcohol consumption. Blood pressure was higher when measured on the right arm and on Tuesdays. MMM17 was one of the largest BP screening campaigns undertaken in Australia using standardized BP measurements. In line with previous surveys, around one-third of screened adults had hypertension and approximately 40% of treated individuals remained uncontrolled. These results suggest that opportunistic screening can identify significant numbers with raised BP.

16.
BMC Complement Altern Med ; 19(1): 234, 2019 Aug 29.
Article in English | MEDLINE | ID: mdl-31464643

ABSTRACT

BACKGROUND: The neurobiology of persistent pain shares common underlying psychobiology with that of traumatic stress. Modern treatments for traumatic stress often involve bottom-up sensorimotor retraining/exposure therapies, where breath, movement, balance and mindfulness, are used to target underlying psychobiology. Vigorous exercise, in particular Bikram yoga, combines many of these sensorimotor/exposure therapeutic features. However, there is very little research investigating the feasibility and efficacy of such treatments for targeting the underlying psychobiology of persistent pain. METHODS: This study was a randomized controlled trail (RCT) comparing the efficacy of Bikram yoga versus high intensity interval training (HIIT), for improving persistent pain in women aged 20 to 50 years. The participants were 1:1 randomized to attend their assigned intervention, 3 times per week, for 8 weeks. The primary outcome measure was the Brief Pain Inventory (BPI) and further pain related biopsychosocial secondary outcomes, including SF-36 Medical Outcomes and heart rate variability (HRV), were also explored. Data was collected pre (t0) and post (t1) intervention via an online questionnaire and physiological testing. RESULTS: A total of 34 women were recruited from the community. Analyses using ANCOVA demonstrated no significant difference in BPI (severity plus interference) scores between the Bikram yoga (n = 17) and the HIIT (n = 15). Women in the Bikram yoga group demonstrated significantly improved SF-36 subscale physical functioning: [ANCOVA: F(1, 29) = 6.17, p = .019, partial eta-squared effect size (ηp2) = .175 and mental health: F(1, 29) = 9.09, p = .005, ηp2 = .239; and increased heart rate variability (SDNN): F(1, 29) = 5.12, p = .013, ηp2 = .150, scores compared to the HIIT group. Across both groups, pain was shown to decrease, no injuries were experienced and retention rates were 94% for Bikram yoga and 75% for HIIT . CONCLUSIONS: Bikram yoga does not appear a superior exercise compared to HIIT for persistent pain. However, imporvements in quality of life measures and indicator of better health were seen in the Bikram yoga group. The outcomes of the present study suggest vigorous exercise interventions in persistent pain cohorts are feasible. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ( ACTRN12617001507370 , 26/10/2017).


Subject(s)
Chronic Pain , Exercise Therapy , High-Intensity Interval Training , Wounds and Injuries/complications , Yoga , Adult , Chronic Pain/etiology , Chronic Pain/therapy , Feasibility Studies , Female , Humans , Middle Aged , Pilot Projects , Young Adult
17.
Heart Lung Circ ; 28(7): 1082-1089, 2019 Jul.
Article in English | MEDLINE | ID: mdl-30931916

ABSTRACT

BACKGROUND: Twenty-four-hour (24-hr) ambulatory blood pressure monitoring (ABPM) is often considered the gold standard to detect hypertension. We aimed to determine the short-term progression of 24-hour blood pressure after coarctation repair and to compare ABPM between two different devices. METHODS: We performed a cross-sectional study using 24-hour ABPM (Oscar 2) in 47 patients aged 16-48 years with previous paediatric coarctation repair and not on antihypertensive medication. Results were compared to a previous ABPM using paired analyses. A subset (10/47, 21%) had an additional previous ABPM performed using a Spacelabs device. RESULTS: After a mean follow-up of 27±6 years after repair, hypertension and prehypertension on Oscar 2 ABPM was present in 57% (27/47) and 11% (5/47), respectively. Mean follow-up time between Oscar 2 ABPMs was 3.9±1.4 years, and between first Oscar 2 and Spacelabs and between Spacelabs and second Oscar 2 ABPM was 1.4±0.8 and 1.8±0.3 years, respectively. There was no difference in the proportion of hypertensive patients between Oscar 2 ABPMs (55% [26/47] vs. 57% [27/47], p=1.0) but 17 patients (17/47, 36%) had a reclassification of 24-hour ABPM status. Mean 24-hour systolic blood pressure was higher in both Oscar 2 ABPMs compared to Spacelabs (142.4±11.7 vs. 120.4±11.8mmHg, p=0.0001; and 137.4±12.2 vs. 120.4±11.8mmHg, p=0.0001; respectively). CONCLUSION: There was high intra-device reproducibility of 24-hour ABPM results using an Oscar 2 device but poor inter-device reproducibility in patients with repaired coarctation. Device-specific reference values may be required to ensure reliable 24-hour ABPM interpretation.


Subject(s)
Antihypertensive Agents/administration & dosage , Aortic Coarctation , Blood Pressure Monitoring, Ambulatory , Blood Pressure/drug effects , Hypertension , Postoperative Complications , Vascular Surgical Procedures/adverse effects , Adult , Aortic Coarctation/physiopathology , Aortic Coarctation/surgery , Child, Preschool , Cross-Sectional Studies , Female , Follow-Up Studies , Humans , Hypertension/drug therapy , Hypertension/ethnology , Hypertension/physiopathology , Infant , Infant, Newborn , Male , Postoperative Complications/drug therapy , Postoperative Complications/physiopathology , Reproducibility of Results
18.
Diabetologia ; 61(1): 220-230, 2018 01.
Article in English | MEDLINE | ID: mdl-29046921

ABSTRACT

AIMS/HYPOTHESIS: Increasing brown adipose tissue (BAT) activity is a possible therapeutic strategy to increase energy expenditure and glucose and lipid clearance to ameliorate obesity and associated comorbidities. The thiazolidinedione (TZD) class of glucose-lowering drugs increase BAT browning in preclinical experimental models but whether these actions extend to humans in vivo is unknown. The aim of this study was to determine the effect of pioglitazone treatment on adipocyte browning and adaptive thermogenesis in humans. METHODS: We first examined whether pioglitazone treatment of cultured human primary subacromioclavicular-derived adipocytes induced browning. Then, in a blinded, placebo-controlled, parallel trial, conducted within the Baker Institute clinical research laboratories, 14 lean male participants who were free of cardiometabolic disease were randomised to receive either placebo (lactose; n = 7, age 22 ± 1 years) or pioglitazone (45 mg/day, n = 7, age 21 ± 1 years) for 28 days. Participants were allocated to treatments by Alfred Hospital staff independent from the study via electronic generation of a random number sequence. Researchers conducting trials and analysing data were blind to treatment allocation. The change in cold-stimulated BAT activity, assessed before and after the intervention by [18F]fluorodeoxyglucose uptake via positron emission tomography/computed tomography in upper thoracic and cervical adipose tissue, was the primary outcome measure. Energy expenditure, cardiovascular responses, core temperature, blood metabolites and hormones were measured in response to acute cold exposure along with body composition before and after the intervention. RESULTS: Pioglitazone significantly increased in vitro browning and adipogenesis of adipocytes. In the clinical trial, cold-induced BAT maximum standardised uptake value was significantly reduced after pioglitazone compared with placebo (-57 ± 6% vs -12 ± 18%, respectively; p < 0.05). BAT total glucose uptake followed a similar but non-significant trend (-50 ± 10% vs -6 ± 24%, respectively; p = 0.097). Pioglitazone increased total and lean body mass compared with placebo (p < 0.05). No other changes between groups were detected. CONCLUSIONS/INTERPRETATION: The disparity in the actions of pioglitazone on BAT between preclinical experimental models and our in vivo human trial highlight the imperative to conduct human proof-of-concept studies as early as possible in BAT research programmes aimed at therapeutic development. Our clinical trial findings suggest that reduced BAT activity may contribute to weight gain associated with pioglitazone and other TZDs. TRIAL REGISTRATION: ClinicalTrials.gov NCT02236962 FUNDING: This work was supported by the Diabetes Australia Research Program and OIS scheme from the Victorian State Government.


Subject(s)
Obesity/drug therapy , Thiazolidinediones/therapeutic use , Adipocytes/drug effects , Adipose Tissue, Brown/drug effects , Adipose Tissue, Brown/metabolism , Adult , Body Composition/drug effects , Cold Temperature , Energy Metabolism/drug effects , Female , Humans , Male , Pioglitazone , Positron-Emission Tomography , Thermogenesis/drug effects , Young Adult
19.
Diabetologia ; 61(2): 504-505, 2018 02.
Article in English | MEDLINE | ID: mdl-29222583

ABSTRACT

The baseline insulin data given in Table 1 for the placebo group were incorrectly reported as 51 ± 10 pmol/l instead of 48 ± 10 pmol/l. This mistake also impacts on data reported in Table 4.

20.
Am J Physiol Heart Circ Physiol ; 315(2): H340-H347, 2018 08 01.
Article in English | MEDLINE | ID: mdl-29701999

ABSTRACT

Patients with heart failure (HF) have increased levels of cardiac norepinephrine (NE) spillover, which is an independent predictor of mortality. We hypothesized that this increase in NE spillover in HF depends not only on increases in sympathetic nerve activity (SNA) but also on changes in the mechanisms controlling NE release and reuptake. Such changes would lead to differences between the increases in directly recorded SNA and NE spillover to the heart in HF. Experiments were conducted in conscious sheep implanted with electrodes to record cardiac SNA (CSNA). In addition, arterial pressure and cardiac NE spillover were determined. In HF, the levels of both CSNA (102 ± 8 vs. 45 ± 8 bursts/min, P < 0.05) and cardiac NE spillover (21.6 ± 3.8 vs. 3.9 ± 0.8 pmol/min, P < 0.05) were significantly higher than in normal control animals. In HF, baroreflex control of cardiac NE spillover was impaired, and when CSNA was abolished by increasing arterial pressure, there was no reduction in cardiac NE spillover. A decrease in cardiac filling pressures in the HF group led to a significant increase in CSNA, but it significantly decreased cardiac NE spillover. In HF, the levels of cardiac NE spillover were enhanced above those expected from the high level of SNA, suggesting that changes in mechanisms controlling NE release and reuptake further increase the high level of NE at the heart, which will act to enhance the deleterious effects of increased CSNA in HF. NEW & NOTEWORTHY This is the first study, to our knowledge, to compare direct recordings of cardiac sympathetic nerve activity with simultaneously measured cardiac norepinephrine (NE) spillover. Our results indicate that in heart failure, increased cardiac sympathetic nerve activity is a major contributor to the increased NE spillover. In addition, there is enhanced NE spillover for the levels of synaptic nerve activity.


Subject(s)
Heart Failure/metabolism , Norepinephrine/metabolism , Animals , Blood Pressure , Female , Heart/innervation , Heart/physiopathology , Heart Failure/physiopathology , Myocardium/metabolism , Sheep , Sympathetic Nervous System/physiology
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